Capacitors: types, charging/discharging, and applications MCQs

Q1: Which of the following is NOT a type of capacitor?
(A) Ceramic capacitor
(B) Electrolytic capacitor
(C) Inductive capacitor
(D) Tantalum capacitor
Answer: (C) Inductive capacitor

Q2: Which type of capacitor is polarized?
(A) Ceramic capacitor
(B) Electrolytic capacitor
(C) Mica capacitor
(D) Film capacitor
Answer: (B) Electrolytic capacitor

Q3: Tantalum capacitors are preferred for:
(A) High-frequency applications
(B) Low-voltage applications
(C) Large capacitance in small sizes
(D) High-temperature environments
Answer: (C) Large capacitance in small sizes

Q4: Which type of capacitor is typically used in high-frequency applications?
(A) Ceramic capacitor
(B) Electrolytic capacitor
(C) Tantalum capacitor
(D) Paper capacitor
Answer: (A) Ceramic capacitor

Q5: Which capacitor has the highest energy storage capacity for a given size?
(A) Film capacitor
(B) Ceramic capacitor
(C) Supercapacitor
(D) Mica capacitor
Answer: (C) Supercapacitor

Q6: When a capacitor is fully charged, the voltage across it is:
(A) Equal to the supply voltage
(B) Zero
(C) Twice the supply voltage
(D) Infinite
Answer: (A) Equal to the supply voltage

Q7: The time constant of a capacitor is given by:
(A) $tau = R times C$
(B) $tau = R / C$
(C) $tau = R + C$
(D) $tau = R – C$
Answer: (A) $tau = R times C$

Q8: During the charging of a capacitor, the current through the capacitor:
(A) Increases exponentially
(B) Decreases exponentially
(C) Remains constant
(D) Becomes zero instantly
Answer: (B) Decreases exponentially

Q9: During the discharging of a capacitor, the voltage across it:
(A) Increases exponentially
(B) Decreases exponentially
(C) Remains constant
(D) Becomes zero instantly
Answer: (B) Decreases exponentially

Q10: In an RC circuit, the voltage across the capacitor during charging is given by:
(A) $V_c = V_0 e^{-t/RC}$
(B) $V_c = V_0 (1 – e^{-t/RC})$
(C) $V_c = V_0 + e^{-t/RC}$
(D) $V_c = e^{t/RC}$
Answer: (B) $V_c = V_0 (1 – e^{-t/RC})$

Q11: Capacitors are used in electronic circuits to:
(A) Store energy
(B) Block DC and allow AC
(C) Smooth voltage fluctuations
(D) All of the above
Answer: (D) All of the above

Q12: Which type of capacitor is typically used for energy storage in renewable energy systems?
(A) Ceramic capacitor
(B) Film capacitor
(C) Supercapacitor
(D) Mica capacitor
Answer: (C) Supercapacitor

Q13: Capacitors are used in power supply circuits to:
(A) Amplify signals
(B) Filter ripples in the output
(C) Generate DC from AC
(D) Store charge permanently
Answer: (B) Filter ripples in the output

Q14: In audio circuits, capacitors are often used to:
(A) Block low-frequency signals
(B) Block high-frequency signals
(C) Couple or decouple signals
(D) Amplify sound signals
Answer: (C) Couple or decouple signals

Q15: Which of the following is NOT a typical application of capacitors?
(A) Tuning circuits
(B) Energy storage
(C) Current amplification
(D) Power factor correction
Answer: (C) Current amplification